Should Obama or Trump Pick Scalia’s Replacement?

President Obama is to confer in the Oval Office on Tuesday with Senator Mitch McConnell of Kentucky, the Republican majority leader, and Senator Charles E. Grassley of Iowa, the Republican chairman of the Senate Judiciary Committee, about filling the Supreme Court vacancy left by the death of Justice Antonin Scalia. If everyone maintains previously stated positions, it might be a very short meeting.

One aide to a vulnerable Senate Republican, who requested anonymity, jokingly suggested that there might be another, very different source of pressure as early as Tuesday night. “I’m not sure we want to be in the business of telling voters that we’d rather risk having Donald Trump nominate the next Supreme Court justice,” he said.